1. Field of the Invention
This invention relates to materials that can be applied to or added with cementitious matter to improve the strength and resistance to deterioration thereof. Still more particularly, this invention relates to a material which when added to cementitious matter containing reinforcing therein, will subsequently prevent and delay the corrosion thereof. Even more particularly, this invention relates to materials which when used with cementious matter is safe to use and relatively harmless to the environment.
2. Discussion of the Prior Art
There is a pressing need in the construction industry to prevent corrosion due to time and pollution from occurring. For example, in road and bridge construction where vast amounts of reinforced concrete is poured, considerable damage occurs by road use and pollution. Additionally, in some areas of the world, areas where roads encounter snow and ice, considerable matter is applied to reduce said snow and ice conditions. Materials such as salts are commonly used to reduce these conditions. If the road bed or bridges have cracks and such within the material or surfaces, the salt and pollution can seep down inside the cementitious matter and reach the reinforcing (e.g. steel rods) imbedded therein. Corrosion thus occurs and this results in a "blooming" of the cementitious matter. This is highly undesirable and much repair work must take place when this happens.
Yet other cementitious material such as monuments, works of arts, tombstones, slate and tile roofs, remainders of antiquity and the like, will decay over time. It is desirable to be able to prevent this from happening and to preserve this matter as long as possible. Much of this corrosion or deterioration happens because of pollutants such as acid rain.
Conventional, cementitious (concrete) structures are commonly used throughout the world by the construction industry. Many of these structures use metal reinforcing materials (e.g. re-bar) to insure that the structural integrity is maintained. However, many of these structures undergo considerable corrosion when penetrated by deleterious chemical materials such as that found in air pollution or that applied to the surfaces of roads, bridges and the like to reduce the effect of ice and snow, for example. The corrosion products in and around the reinforcing steel causes cracks to develop in the cementitious material thus allow even more intrusion of these deleterious materials and acceleration of the subsequent corrosion. This corrosion is sometimes called "spalling" and tends to diminish the structural integrity of any reinforcing member placed therein. Eventually, complete failure of the concrete structure occurs. All of this is extremely undesirable within the construction industry and there is a long standing need to find methods for reducing or even eliminating these corrosion effects.
The use of silicates and related material for use in the coating of cementitious matter is well-known. These prior art references teach the use of particular ratios of potassium or sodium silicates, for example, to coat and water-proof already existing structures made from cementitious matter. Still other references teach the use of silicates for the encapsulation of contaminated or polluted matter that may include cementitious matter. Most of these prior art coatings are not particularly effective in preserving the cementitious matter on which they are applied. In fact, although most of these references do infer that some preservation is achieved, many fail miserably to attain the requisite levels so highly desired by the building industry.
Thus, it is a long sought-after goal to provide a safe, inexpensive and effective material that can be applied on or mixed with cementitious matter to prevent the aforesaid deterioration.